Five people have been arrested in London for online attacks in support of WikiLeaks. The five, three of them teenagers, are suspected of belonging to a group that considered corporate targets hostile to WikiLeaks.

According to the Metropolitan Police Service, the five, ages 15 to 26, are associated with the group Anonymous. While details haven't been released, the arrests are expected to be related to denial-of-service attacks, dubbed Operation Payback by the group, on PayPal, MasterCard, Visa and Moneybookers. The target companies had refused to process online donations to WikiLeaks following its unauthorized release of U.S. diplomatic cables.

Tunisia, Egypt

The arrests were made in the West Midlands, Northamptonshire, Hertfordshire, Surrey and London. In December, police in Holland arrested two teenagers also suspected of being involved in Operation Payback. Observers suspect the raids in both countries were made in cooperation with the U.S. Department of Justice. U.S. Attorney General Eric Holder said last month that his agency was investigating the attacks.

The Anonymous group has been in the news recently for other incidents, including online attacks earlier this month on Tunisia's government, including its official web site and the site of the country's stock exchange. Tunisia has been racked by demonstrations against the current regime.

Anonymous has also issued warnings of online reprisals against the Egyptian government if it attempts to block Internet access by protesters in that country.

In both the corporate and government attacks, a key technique was apparently to distribute software, via chat rooms and other venues, that could be utilized to jam servers in a distributed denial-of-service attack.

N.Y. Times, The Guardian, Der Spiegel

In 2010, Pfc. Bradley Manning, an Army intelligence analyst, reportedly admitted to an ex-hacker he met online that he had downloaded hundreds of thousands of documents from the U.S. military's network to a CD he labeled Lady Gaga.

The classified U.S. diplomatic cables were then turned over to WikiLeaks, which posted them, and some of the contents have since been published by The New York Times, The Guardian in the U.K., Der Spiegel, Le Monde, and other publications. Manning, who was stationed in Iraq, was arrested by the Army's Criminal Investigation Division.

Manning is also accused of being the source of a video posted on WikiLeaks in April that showed a U.S. air strike in Iraq that took the lives of several civilians.

Following publication of the leaked documents, WikiLeaks had its accounts shut down by Amazon.com, PayPal, Visa and MasterCard, and founder Julian Assange was arrested in the U.K. on an unrelated charge, which he has said is politically motivated.